public void VerifyEncoding_largecorpus()
{
string input = TestResources.RFC5_Text;
int len = input.Length;
var data = new MemoryStream();
var writer = new BitBinaryWriter(data);
var reader = new BitBinaryReader(data);
var compressor = new DynamicHuffman <char>(OriginalNYT);
for (int i = 0; i < len; ++i)
{
compressor.WriteCode(input[i], writer.Write, writer.Write);
}
writer.Flush();
data.Position = 0;
var decompressor = new DynamicHuffman <char>(OriginalNYT);
for (int i = 0; i < len; ++i)
{
Assert.AreEqual(input[i], decompressor.GetSymbol(reader.ReadBoolean, reader.ReadChar));
}
Assert.AreEqual(data.Position, data.Length);
}
public void BaseStream_NotBitStream()
{
var data = new byte[] { 0x23, 0x72, 0x64, 0xe3, 0x11, 0xd1, 0x4a, 0x9c, 0xb6, 0x02 };
var stream = new MemoryStream(data);
var writer = new BitBinaryWriter(stream);
Assert.AreNotSame(stream, writer.BaseStream);
}
private static bool WriteDouble(BitBinaryWriter writer, double value, DoubleValueState previousValue, out DoubleValueState newValue)
{
newValue = previousValue;
newValue.Value = value;
var xor = BitConverter.DoubleToInt64Bits(value) ^ BitConverter.DoubleToInt64Bits(previousValue.Value);
if (xor == 0)
{
writer.WriteBit(false);
}
else
{
writer.WriteBit(true);
var leadingZeros = (sbyte)BitAggregateMagic.CountLeadingZeros(xor);
var trailingZeros = (sbyte)BitAggregateMagic.CountTrailingZeros(xor);
if (leadingZeros > MaxLeadingZerosLength)
{
leadingZeros = MaxLeadingZerosLength;
}
int blockSize = 64 - leadingZeros - trailingZeros;
int expectedSize = NumBitsToEncodeNumLeadingZeros + NumBitsToEncodeNumMeaningfulBits + blockSize;
int previousBlockInformationSize = 64 - previousValue.TrailingZeros - previousValue.LeadingZeros;
// The block position is set by the first non-zero XOR value. previousValue.LeadingZeros was initialized to -1s to start with.
if (previousValue.LeadingZeros > 0 && leadingZeros >= previousValue.LeadingZeros && trailingZeros >= previousValue.TrailingZeros && previousBlockInformationSize < expectedSize)
{
writer.WriteBit(false);
// there are at least as many leading zeros and as many trailing zeros as with the previous value, reuse the block position.
var numMeaningfulBits = BitAggregateMagic.NumBitsInLongInteger - previousValue.LeadingZeros - previousValue.TrailingZeros;
writer.WriteBits(xor, numMeaningfulBits, previousValue.TrailingZeros);
}
else
{
// start a new block position
writer.WriteBit(true);
writer.WriteBits(leadingZeros, NumBitsToEncodeNumLeadingZeros, 0);
newValue.LeadingZeros = leadingZeros;
var numMeaningfulBits = BitAggregateMagic.NumBitsInLongInteger - leadingZeros - trailingZeros;
writer.WriteBits(numMeaningfulBits, NumBitsToEncodeNumMeaningfulBits, 0);
newValue.TrailingZeros = trailingZeros;
writer.WriteBits(xor, numMeaningfulBits, trailingZeros);
}
}
return(true);
}
public void BitBinaryWriterCompatible()
{
var stream = new MemoryStream();
var writer = new BitBinaryWriter(stream);
var reader = new BitBinaryReader(stream);
foreach (TestValue value in _testValuesWithBits)
{
value.Write(writer);
}
writer.Flush();
stream.Position = 0;
foreach (TestValue value in _testValuesWithBits)
{
value.Read(reader);
}
}
public static unsafe void Serialize(BinaryWriter writer, double *values, int count)
{
// Reserve one byte for future versioning.
writer.Write((byte)1);
SerializationUtils.WriteUInt32AsBase128(writer, (uint)count);
if (count > 0)
{
BitBinaryWriter bitWriter = new BitBinaryWriter(writer);
var previousState = new DoubleValueState(0, -1, -1);
for (int i = 0; i < count; ++i)
{
DoubleValueState newState;
WriteDouble(bitWriter, values[i], previousState, out newState);
previousState = newState;
}
bitWriter.Flush();
}
}
public void VerifyEncoding_astrachan_()
{
string input = "astrachan_";
var data = new MemoryStream();
var writer = new BitBinaryWriter(data);
var reader = new BitBinaryReader(data);
var compressor = new DynamicHuffman <char>(OriginalNYT);
for (int i = 0; i < input.Length; ++i)
{
compressor.WriteCode(input[i], writer.Write, writer.Write);
}
writer.Flush();
data.Position = 0;
var decompressor = new DynamicHuffman <char>(OriginalNYT);
for (int i = 0; i < input.Length; ++i)
{
Assert.AreEqual(input[i], decompressor.GetSymbol(reader.ReadBoolean, reader.ReadChar));
}
Assert.AreEqual(data.Position, data.Length);
}
